图像细化算法 opencv实现 完整代码（附实验结果）

一、关于图像细化的算法可以参看下面两个PDF链接：

http://www.uel.br/pessoal/josealexandre/stuff/thinning/ftp/lam-lee-survey.pdf  ：总结了几乎所有92年以前的经典细化算法

http://www-prima.inrialpes.fr/perso/Tran/Draft/gateway.cfm.pdf ：本文所附代码所参照的算法

二、实验结果

原图：

运行结果（分别为迭代1次、4次、8次、16次、64次的结果图）：

三、opencv代码

运行环境：Windows 7，VS 2012，OpenCV 2.3

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <fstream>
#include <string>
#include <iostream>
#include <opencv/cv.h>
#include <opencv/highgui.h> 
using namespace std; 

void cvThin( IplImage*, IplImage*, int iterations);

//使用举例

int main(int argc, char* argv[])
{
 IplImage *pSrc = NULL,*pDst = NULL,*pTmp = NULL;

//传入一个灰度图像     
 pSrc = cvLoadImage("1.bmp",CV_LOAD_IMAGE_GRAYSCALE);
 if(!pSrc)
 {
  return 0;
 }

 pTmp = cvCloneImage(pSrc);
 pDst = cvCreateImage(cvGetSize(pSrc),pSrc->depth,pSrc->nChannels);
 cvZero(pDst);
 cvThreshold(pSrc,pTmp,68,1,CV_THRESH_BINARY_INV);//做二值处理，将图像转换成0，1格式
 
 //cvSaveImage("pTmp.bmp",pTmp);

 cvThin(pTmp,pDst,8);//细化，通过修改iterations参数进一步细化

 cvNamedWindow("src",1);
 cvNamedWindow("dst",1);
 cvShowImage("src",pSrc);

 //将二值图像转换成灰度，以便显示
 int i = 0,j = 0;
 CvSize size = cvGetSize(pDst);
 for(i=0; i<size.height;  i++)
 {
  for(j=0; j<size.width; j++)
  {
   if(CV_IMAGE_ELEM(pDst,uchar,i,j)==1)
   {
    CV_IMAGE_ELEM(pDst,uchar,i,j) = 0;
   }
   else
   {
    CV_IMAGE_ELEM(pDst,uchar,i,j) = 255;
   }
  }
 }
 cvSaveImage("dst_8.bmp",pDst);

 cvShowImage("dst",pDst);
 cvWaitKey(0);

 cvReleaseImage(&pSrc);
 cvReleaseImage(&pDst);
 cvReleaseImage(&pTmp);

 cvDestroyWindow("src");
 cvDestroyWindow("dst");

 return 0;
}


void cvThin( IplImage* src, IplImage* dst, int iterations)
{
 //此时的src是一个二值化的图片
 CvSize size = cvGetSize(src);
 cvCopy(src, dst);

 int n = 0,i = 0,j = 0;
 for(n=0; n<iterations; n++)//开始进行迭代
 {
   IplImage* t_image = cvCloneImage(dst);
   for(i=0; i<size.height;  i++)
  {
   for(j=0; j<size.width; j++)
   {
    if(CV_IMAGE_ELEM(t_image,byte,i,j)==1)
    {
     int ap=0;
     int p2 = (i==0)?0:CV_IMAGE_ELEM(t_image,byte, i-1, j);
     int p3 = (i==0 || j==size.width-1)?0:CV_IMAGE_ELEM(t_image,byte, i-1, j+1);
     if (p2==0 && p3==1)
     {
      ap++;
     }

     int p4 = (j==size.width-1)?0:CV_IMAGE_ELEM(t_image,byte,i,j+1);
     if(p3==0 && p4==1)
     {
      ap++;
     }

     int p5 = (i==size.height-1 || j==size.width-1)?0:CV_IMAGE_ELEM(t_image,byte,i+1,j+1);
     if(p4==0 && p5==1)
     {
      ap++;
     }

     int p6 = (i==size.height-1)?0:CV_IMAGE_ELEM(t_image,byte,i+1,j);
     if(p5==0 && p6==1)
     {
      ap++;
     }

     int p7 = (i==size.height-1 || j==0)?0:CV_IMAGE_ELEM(t_image,byte,i+1,j-1);
     if(p6==0 && p7==1)
     {
      ap++;
     }

     int p8 = (j==0)?0:CV_IMAGE_ELEM(t_image,byte,i,j-1);
     if(p7==0 && p8==1)
     {
      ap++;
     }

     int p9 = (i==0 || j==0)?0:CV_IMAGE_ELEM(t_image,byte,i-1,j-1);
     if(p8==0 && p9==1)
     {
      ap++;
     }
     if(p9==0 && p2==1)
     {
      ap++;
     }

     if((p2+p3+p4+p5+p6+p7+p8+p9)>1 && (p2+p3+p4+p5+p6+p7+p8+p9)<7)
     {
      if(ap==1)
      {
       if(!(p2 && p4 && p6))
       {
        if(!(p4 && p6 && p8)) 
        {
         CV_IMAGE_ELEM(dst,byte,i,j)=0;//设置目标图像中像素值为0的点
        }
       }
      }
     }

    }
   }
  }

  cvReleaseImage(&t_image);

  t_image = cvCloneImage(dst);
  for(i=0; i<size.height;  i++)
  {
   for(int j=0; j<size.width; j++)
   {
    if(CV_IMAGE_ELEM(t_image,byte,i,j)==1)
    {
     int ap=0;
     int p2 = (i==0)?0:CV_IMAGE_ELEM(t_image,byte, i-1, j);
     int p3 = (i==0 || j==size.width-1)?0:CV_IMAGE_ELEM(t_image,byte, i-1, j+1);
     if (p2==0 && p3==1)
     {
      ap++;
     }
     int p4 = (j==size.width-1)?0:CV_IMAGE_ELEM(t_image,byte,i,j+1);
     if(p3==0 && p4==1)
     {
      ap++;
     }
     int p5 = (i==size.height-1 || j==size.width-1)?0:CV_IMAGE_ELEM(t_image,byte,i+1,j+1);
     if(p4==0 && p5==1)
     {
      ap++;
     }
     int p6 = (i==size.height-1)?0:CV_IMAGE_ELEM(t_image,byte,i+1,j);
     if(p5==0 && p6==1)
     {
      ap++;
     }
     int p7 = (i==size.height-1 || j==0)?0:CV_IMAGE_ELEM(t_image,byte,i+1,j-1);
     if(p6==0 && p7==1)
     {
      ap++;
     }
     int p8 = (j==0)?0:CV_IMAGE_ELEM(t_image,byte,i,j-1);
     if(p7==0 && p8==1)
     {
      ap++;
     }
     int p9 = (i==0 || j==0)?0:CV_IMAGE_ELEM(t_image,byte,i-1,j-1);
     if(p8==0 && p9==1)
     {
      ap++;
     }
     if(p9==0 && p2==1)
     {
      ap++;
     }
     if((p2+p3+p4+p5+p6+p7+p8+p9)>1 && (p2+p3+p4+p5+p6+p7+p8+p9)<7)
     {
      if(ap==1)
      {
       if(p2*p4*p8==0)
       {
        if(p2*p6*p8==0)
        {
         CV_IMAGE_ELEM(dst, byte,i,j)=0;
        }
       }
      }
     }                    
    }

   }

  }            
  cvReleaseImage(&t_image);
 }

}

四、参考链接

[1]http://tech.groups.yahoo.com/group/OpenCV/message/70260

[2]http://blog.csdn.net/byxdaz/article/details/5642669